net/wireless/scan.c

   1 /*
   2  * cfg80211 scan result handling
   3  *
   4  * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
   5  */
   6 #include <linux/kernel.h>
   7 #include <linux/slab.h>
   8 #include <linux/module.h>
   9 #include <linux/netdevice.h>
  10 #include <linux/wireless.h>
  11 #include <linux/nl80211.h>
  12 #include <linux/etherdevice.h>
  13 #include <net/arp.h>
  14 #include <net/cfg80211.h>
  15 #include <net/cfg80211-wext.h>
  16 #include <net/iw_handler.h>
  17 #include "core.h"
  18 #include "nl80211.h"
  19 #include "wext-compat.h"
  20
  21 #define IEEE80211_SCAN_RESULT_EXPIRE    (30 * HZ)
  22
  23 void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, bool leak)
  24 {
  25         struct cfg80211_scan_request *request;
  26         struct wireless_dev *wdev;
  27 #ifdef CONFIG_CFG80211_WEXT
  28         union iwreq_data wrqu;
  29 #endif
  30
  31         ASSERT_RDEV_LOCK(rdev);
  32
  33         request = rdev->scan_req;
  34
  35         if (!request)
  36                 return;
  37
  38         wdev = request->wdev;
  39
  40         /*
  41          * This must be before sending the other events!
  42          * Otherwise, wpa_supplicant gets completely confused with
  43          * wext events.
  44          */
  45         if (wdev->netdev)
  46                 cfg80211_sme_scan_done(wdev->netdev);
  47
  48         if (request->aborted)
  49                 nl80211_send_scan_aborted(rdev, wdev);
  50         else
  51                 nl80211_send_scan_done(rdev, wdev);
  52
  53 #ifdef CONFIG_CFG80211_WEXT
  54         if (wdev->netdev && !request->aborted) {
  55                 memset(&wrqu, 0, sizeof(wrqu));
  56
  57                 wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
  58         }
  59 #endif
  60
  61         if (wdev->netdev)
  62                 dev_put(wdev->netdev);
  63
  64         rdev->scan_req = NULL;
  65
  66         /*
  67          * OK. If this is invoked with "leak" then we can't
  68          * free this ... but we've cleaned it up anyway. The
  69          * driver failed to call the scan_done callback, so
  70          * all bets are off, it might still be trying to use
  71          * the scan request or not ... if it accesses the dev
  72          * in there (it shouldn't anyway) then it may crash.
  73          */
  74         if (!leak)
  75                 kfree(request);
  76 }
  77
  78 void __cfg80211_scan_done(struct work_struct *wk)
  79 {
  80         struct cfg80211_registered_device *rdev;
  81
  82         rdev = container_of(wk, struct cfg80211_registered_device,
  83                             scan_done_wk);
  84
  85         cfg80211_lock_rdev(rdev);
  86         ___cfg80211_scan_done(rdev, false);
  87         cfg80211_unlock_rdev(rdev);
  88 }
  89
  90 void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
  91 {
  92         WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
  93
  94         request->aborted = aborted;
  95         queue_work(cfg80211_wq, &wiphy_to_dev(request->wiphy)->scan_done_wk);
  96 }
  97 EXPORT_SYMBOL(cfg80211_scan_done);
  98
  99 void __cfg80211_sched_scan_results(struct work_struct *wk)
 100 {
 101         struct cfg80211_registered_device *rdev;
 102
 103         rdev = container_of(wk, struct cfg80211_registered_device,
 104                             sched_scan_results_wk);
 105
 106         mutex_lock(&rdev->sched_scan_mtx);
 107
 108         /* we don't have sched_scan_req anymore if the scan is stopping */
 109         if (rdev->sched_scan_req)
 110                 nl80211_send_sched_scan_results(rdev,
 111                                                 rdev->sched_scan_req->dev);
 112
 113         mutex_unlock(&rdev->sched_scan_mtx);
 114 }
 115
 116 void cfg80211_sched_scan_results(struct wiphy *wiphy)
 117 {
 118         /* ignore if we're not scanning */
 119         if (wiphy_to_dev(wiphy)->sched_scan_req)
 120                 queue_work(cfg80211_wq,
 121                            &wiphy_to_dev(wiphy)->sched_scan_results_wk);
 122 }
 123 EXPORT_SYMBOL(cfg80211_sched_scan_results);
 124
 125 void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
 126 {
 127         struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
 128
 129         mutex_lock(&rdev->sched_scan_mtx);
 130         __cfg80211_stop_sched_scan(rdev, true);
 131         mutex_unlock(&rdev->sched_scan_mtx);
 132 }
 133 EXPORT_SYMBOL(cfg80211_sched_scan_stopped);
 134
 135 int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
 136                                bool driver_initiated)
 137 {
 138         struct net_device *dev;
 139
 140         lockdep_assert_held(&rdev->sched_scan_mtx);
 141
 142         if (!rdev->sched_scan_req)
 143                 return -ENOENT;
 144
 145         dev = rdev->sched_scan_req->dev;
 146
 147         if (!driver_initiated) {
 148                 int err = rdev->ops->sched_scan_stop(&rdev->wiphy, dev);
 149                 if (err)
 150                         return err;
 151         }
 152
 153         nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);
 154
 155         kfree(rdev->sched_scan_req);
 156         rdev->sched_scan_req = NULL;
 157
 158         return 0;
 159 }
 160
 161 static void bss_release(struct kref *ref)
 162 {
 163         struct cfg80211_internal_bss *bss;
 164
 165         bss = container_of(ref, struct cfg80211_internal_bss, ref);
 166         if (bss->pub.free_priv)
 167                 bss->pub.free_priv(&bss->pub);
 168
 169         if (bss->beacon_ies_allocated)
 170                 kfree(bss->pub.beacon_ies);
 171         if (bss->proberesp_ies_allocated)
 172                 kfree(bss->pub.proberesp_ies);
 173
 174         BUG_ON(atomic_read(&bss->hold));
 175
 176         kfree(bss);
 177 }
 178
 179 /* must hold dev->bss_lock! */
 180 void cfg80211_bss_age(struct cfg80211_registered_device *dev,
 181                       unsigned long age_secs)
 182 {
 183         struct cfg80211_internal_bss *bss;
 184         unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
 185
 186         list_for_each_entry(bss, &dev->bss_list, list) {
 187                 bss->ts -= age_jiffies;
 188         }
 189 }
 190
 191 /* must hold dev->bss_lock! */
 192 static void __cfg80211_unlink_bss(struct cfg80211_registered_device *dev,
 193                                   struct cfg80211_internal_bss *bss)
 194 {
 195         list_del_init(&bss->list);
 196         rb_erase(&bss->rbn, &dev->bss_tree);
 197         kref_put(&bss->ref, bss_release);
 198 }
 199
 200 /* must hold dev->bss_lock! */
 201 void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
 202 {
 203         struct cfg80211_internal_bss *bss, *tmp;
 204         bool expired = false;
 205
 206         list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
 207                 if (atomic_read(&bss->hold))
 208                         continue;
 209                 if (!time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE))
 210                         continue;
 211                 __cfg80211_unlink_bss(dev, bss);
 212                 expired = true;
 213         }
 214
 215         if (expired)
 216                 dev->bss_generation++;
 217 }
 218
 219 const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
 220 {
 221         while (len > 2 && ies[0] != eid) {
 222                 len -= ies[1] + 2;
 223                 ies += ies[1] + 2;
 224         }
 225         if (len < 2)
 226                 return NULL;
 227         if (len < 2 + ies[1])
 228                 return NULL;
 229         return ies;
 230 }
 231 EXPORT_SYMBOL(cfg80211_find_ie);
 232
 233 const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
 234                                   const u8 *ies, int len)
 235 {
 236         struct ieee80211_vendor_ie *ie;
 237         const u8 *pos = ies, *end = ies + len;
 238         int ie_oui;
 239
 240         while (pos < end) {
 241                 pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
 242                                        end - pos);
 243                 if (!pos)
 244                         return NULL;
 245
 246                 if (end - pos < sizeof(*ie))
 247                         return NULL;
 248
 249                 ie = (struct ieee80211_vendor_ie *)pos;
 250                 ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
 251                 if (ie_oui == oui && ie->oui_type == oui_type)
 252                         return pos;
 253
 254                 pos += 2 + ie->len;
 255         }
 256         return NULL;
 257 }
 258 EXPORT_SYMBOL(cfg80211_find_vendor_ie);
 259
 260 static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2)
 261 {
 262         const u8 *ie1 = cfg80211_find_ie(num, ies1, len1);
 263         const u8 *ie2 = cfg80211_find_ie(num, ies2, len2);
 264
 265         /* equal if both missing */
 266         if (!ie1 && !ie2)
 267                 return 0;
 268         /* sort missing IE before (left of) present IE */
 269         if (!ie1)
 270                 return -1;
 271         if (!ie2)
 272                 return 1;
 273
 274         /* sort by length first, then by contents */
 275         if (ie1[1] != ie2[1])
 276                 return ie2[1] - ie1[1];
 277         return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
 278 }
 279
 280 static bool is_bss(struct cfg80211_bss *a,
 281                    const u8 *bssid,
 282                    const u8 *ssid, size_t ssid_len)
 283 {
 284         const u8 *ssidie;
 285
 286         if (bssid && !ether_addr_equal(a->bssid, bssid))
 287                 return false;
 288
 289         if (!ssid)
 290                 return true;
 291
 292         ssidie = cfg80211_find_ie(WLAN_EID_SSID,
 293                                   a->information_elements,
 294                                   a->len_information_elements);
 295         if (!ssidie)
 296                 return false;
 297         if (ssidie[1] != ssid_len)
 298                 return false;
 299         return memcmp(ssidie + 2, ssid, ssid_len) == 0;
 300 }
 301
 302 static bool is_mesh_bss(struct cfg80211_bss *a)
 303 {
 304         const u8 *ie;
 305
 306         if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 307                 return false;
 308
 309         ie = cfg80211_find_ie(WLAN_EID_MESH_ID,
 310                               a->information_elements,
 311                               a->len_information_elements);
 312         if (!ie)
 313                 return false;
 314
 315         ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 316                               a->information_elements,
 317                               a->len_information_elements);
 318         if (!ie)
 319                 return false;
 320
 321         return true;
 322 }
 323
 324 static bool is_mesh(struct cfg80211_bss *a,
 325                     const u8 *meshid, size_t meshidlen,
 326                     const u8 *meshcfg)
 327 {
 328         const u8 *ie;
 329
 330         if (!WLAN_CAPABILITY_IS_STA_BSS(a->capability))
 331                 return false;
 332
 333         ie = cfg80211_find_ie(WLAN_EID_MESH_ID,
 334                               a->information_elements,
 335                               a->len_information_elements);
 336         if (!ie)
 337                 return false;
 338         if (ie[1] != meshidlen)
 339                 return false;
 340         if (memcmp(ie + 2, meshid, meshidlen))
 341                 return false;
 342
 343         ie = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
 344                               a->information_elements,
 345                               a->len_information_elements);
 346         if (!ie)
 347                 return false;
 348         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
 349                 return false;
 350
 351         /*
 352          * Ignore mesh capability (last two bytes of the IE) when
 353          * comparing since that may differ between stations taking
 354          * part in the same mesh.
 355          */
 356         return memcmp(ie + 2, meshcfg,
 357             sizeof(struct ieee80211_meshconf_ie) - 2) == 0;
 358 }
 359
 360 static int cmp_bss_core(struct cfg80211_bss *a,
 361                         struct cfg80211_bss *b)
 362 {
 363         int r;
 364
 365         if (a->channel != b->channel)
 366                 return b->channel->center_freq - a->channel->center_freq;
 367
 368         if (is_mesh_bss(a) && is_mesh_bss(b)) {
 369                 r = cmp_ies(WLAN_EID_MESH_ID,
 370                             a->information_elements,
 371                             a->len_information_elements,
 372                             b->information_elements,
 373                             b->len_information_elements);
 374                 if (r)
 375                         return r;
 376                 return cmp_ies(WLAN_EID_MESH_CONFIG,
 377                                a->information_elements,
 378                                a->len_information_elements,
 379                                b->information_elements,
 380                                b->len_information_elements);
 381         }
 382
 383         /*
 384          * we can't use compare_ether_addr here since we need a < > operator.
 385          * The binary return value of compare_ether_addr isn't enough
 386          */
 387         return memcmp(a->bssid, b->bssid, sizeof(a->bssid));
 388 }
 389
 390 static int cmp_bss(struct cfg80211_bss *a,
 391                    struct cfg80211_bss *b)
 392 {
 393         int r;
 394
 395         r = cmp_bss_core(a, b);
 396         if (r)
 397                 return r;
 398
 399         return cmp_ies(WLAN_EID_SSID,
 400                        a->information_elements,
 401                        a->len_information_elements,
 402                        b->information_elements,
 403                        b->len_information_elements);
 404 }
 405
 406 static int cmp_hidden_bss(struct cfg80211_bss *a,
 407                    struct cfg80211_bss *b)
 408 {
 409         const u8 *ie1;
 410         const u8 *ie2;
 411         int i;
 412         int r;
 413
 414         r = cmp_bss_core(a, b);
 415         if (r)
 416                 return r;
 417
 418         ie1 = cfg80211_find_ie(WLAN_EID_SSID,
 419                         a->information_elements,
 420                         a->len_information_elements);
 421         ie2 = cfg80211_find_ie(WLAN_EID_SSID,
 422                         b->information_elements,
 423                         b->len_information_elements);
 424
 425         /* Key comparator must use same algorithm in any rb-tree
 426          * search function (order is important), otherwise ordering
 427          * of items in the tree is broken and search gives incorrect
 428          * results. This code uses same order as cmp_ies() does. */
 429
 430         /* sort missing IE before (left of) present IE */
 431         if (!ie1)
 432                 return -1;
 433         if (!ie2)
 434                 return 1;
 435
 436         /* zero-size SSID is used as an indication of the hidden bss */
 437         if (!ie2[1])
 438                 return 0;
 439
 440         /* sort by length first, then by contents */
 441         if (ie1[1] != ie2[1])
 442                 return ie2[1] - ie1[1];
 443
 444         /* zeroed SSID ie is another indication of a hidden bss */
 445         for (i = 0; i < ie2[1]; i++)
 446                 if (ie2[i + 2])
 447                         return -1;
 448
 449         return 0;
 450 }
 451
 452 struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 453                                       struct ieee80211_channel *channel,
 454                                       const u8 *bssid,
 455                                       const u8 *ssid, size_t ssid_len,
 456                                       u16 capa_mask, u16 capa_val)
 457 {
 458         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 459         struct cfg80211_internal_bss *bss, *res = NULL;
 460         unsigned long now = jiffies;
 461
 462         spin_lock_bh(&dev->bss_lock);
 463
 464         list_for_each_entry(bss, &dev->bss_list, list) {
 465                 if ((bss->pub.capability & capa_mask) != capa_val)
 466                         continue;
 467                 if (channel && bss->pub.channel != channel)
 468                         continue;
 469                 /* Don't get expired BSS structs */
 470                 if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
 471                     !atomic_read(&bss->hold))
 472                         continue;
 473                 if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
 474                         res = bss;
 475                         kref_get(&res->ref);
 476                         break;
 477                 }
 478         }
 479
 480         spin_unlock_bh(&dev->bss_lock);
 481         if (!res)
 482                 return NULL;
 483         return &res->pub;
 484 }
 485 EXPORT_SYMBOL(cfg80211_get_bss);
 486
 487 struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
 488                                        struct ieee80211_channel *channel,
 489                                        const u8 *meshid, size_t meshidlen,
 490                                        const u8 *meshcfg)
 491 {
 492         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 493         struct cfg80211_internal_bss *bss, *res = NULL;
 494
 495         spin_lock_bh(&dev->bss_lock);
 496
 497         list_for_each_entry(bss, &dev->bss_list, list) {
 498                 if (channel && bss->pub.channel != channel)
 499                         continue;
 500                 if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
 501                         res = bss;
 502                         kref_get(&res->ref);
 503                         break;
 504                 }
 505         }
 506
 507         spin_unlock_bh(&dev->bss_lock);
 508         if (!res)
 509                 return NULL;
 510         return &res->pub;
 511 }
 512 EXPORT_SYMBOL(cfg80211_get_mesh);
 513
 514
 515 static void rb_insert_bss(struct cfg80211_registered_device *dev,
 516                           struct cfg80211_internal_bss *bss)
 517 {
 518         struct rb_node **p = &dev->bss_tree.rb_node;
 519         struct rb_node *parent = NULL;
 520         struct cfg80211_internal_bss *tbss;
 521         int cmp;
 522
 523         while (*p) {
 524                 parent = *p;
 525                 tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
 526
 527                 cmp = cmp_bss(&bss->pub, &tbss->pub);
 528
 529                 if (WARN_ON(!cmp)) {
 530                         /* will sort of leak this BSS */
 531                         return;
 532                 }
 533
 534                 if (cmp < 0)
 535                         p = &(*p)->rb_left;
 536                 else
 537                         p = &(*p)->rb_right;
 538         }
 539
 540         rb_link_node(&bss->rbn, parent, p);
 541         rb_insert_color(&bss->rbn, &dev->bss_tree);
 542 }
 543
 544 static struct cfg80211_internal_bss *
 545 rb_find_bss(struct cfg80211_registered_device *dev,
 546             struct cfg80211_internal_bss *res)
 547 {
 548         struct rb_node *n = dev->bss_tree.rb_node;
 549         struct cfg80211_internal_bss *bss;
 550         int r;
 551
 552         while (n) {
 553                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 554                 r = cmp_bss(&res->pub, &bss->pub);
 555
 556                 if (r == 0)
 557                         return bss;
 558                 else if (r < 0)
 559                         n = n->rb_left;
 560                 else
 561                         n = n->rb_right;
 562         }
 563
 564         return NULL;
 565 }
 566
 567 static struct cfg80211_internal_bss *
 568 rb_find_hidden_bss(struct cfg80211_registered_device *dev,
 569             struct cfg80211_internal_bss *res)
 570 {
 571         struct rb_node *n = dev->bss_tree.rb_node;
 572         struct cfg80211_internal_bss *bss;
 573         int r;
 574
 575         while (n) {
 576                 bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
 577                 r = cmp_hidden_bss(&res->pub, &bss->pub);
 578
 579                 if (r == 0)
 580                         return bss;
 581                 else if (r < 0)
 582                         n = n->rb_left;
 583                 else
 584                         n = n->rb_right;
 585         }
 586
 587         return NULL;
 588 }
 589
 590 static void
 591 copy_hidden_ies(struct cfg80211_internal_bss *res,
 592                  struct cfg80211_internal_bss *hidden)
 593 {
 594         if (unlikely(res->pub.beacon_ies))
 595                 return;
 596         if (WARN_ON(!hidden->pub.beacon_ies))
 597                 return;
 598
 599         res->pub.beacon_ies = kmalloc(hidden->pub.len_beacon_ies, GFP_ATOMIC);
 600         if (unlikely(!res->pub.beacon_ies))
 601                 return;
 602
 603         res->beacon_ies_allocated = true;
 604         res->pub.len_beacon_ies = hidden->pub.len_beacon_ies;
 605         memcpy(res->pub.beacon_ies, hidden->pub.beacon_ies,
 606                         res->pub.len_beacon_ies);
 607 }
 608
 609 static struct cfg80211_internal_bss *
 610 cfg80211_bss_update(struct cfg80211_registered_device *dev,
 611                     struct cfg80211_internal_bss *res)
 612 {
 613         struct cfg80211_internal_bss *found = NULL;
 614
 615         /*
 616          * The reference to "res" is donated to this function.
 617          */
 618
 619         if (WARN_ON(!res->pub.channel)) {
 620                 kref_put(&res->ref, bss_release);
 621                 return NULL;
 622         }
 623
 624         res->ts = jiffies;
 625
 626         spin_lock_bh(&dev->bss_lock);
 627
 628         found = rb_find_bss(dev, res);
 629
 630         if (found) {
 631                 found->pub.beacon_interval = res->pub.beacon_interval;
 632                 found->pub.tsf = res->pub.tsf;
 633                 found->pub.signal = res->pub.signal;
 634                 found->pub.capability = res->pub.capability;
 635                 found->ts = res->ts;
 636
 637                 /* Update IEs */
 638                 if (res->pub.proberesp_ies) {
 639                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 640                         size_t ielen = res->pub.len_proberesp_ies;
 641
 642                         if (found->pub.proberesp_ies &&
 643                             !found->proberesp_ies_allocated &&
 644                             ksize(found) >= used + ielen) {
 645                                 memcpy(found->pub.proberesp_ies,
 646                                        res->pub.proberesp_ies, ielen);
 647                                 found->pub.len_proberesp_ies = ielen;
 648                         } else {
 649                                 u8 *ies = found->pub.proberesp_ies;
 650
 651                                 if (found->proberesp_ies_allocated)
 652                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 653                                 else
 654                                         ies = kmalloc(ielen, GFP_ATOMIC);
 655
 656                                 if (ies) {
 657                                         memcpy(ies, res->pub.proberesp_ies,
 658                                                ielen);
 659                                         found->proberesp_ies_allocated = true;
 660                                         found->pub.proberesp_ies = ies;
 661                                         found->pub.len_proberesp_ies = ielen;
 662                                 }
 663                         }
 664
 665                         /* Override possible earlier Beacon frame IEs */
 666                         found->pub.information_elements =
 667                                 found->pub.proberesp_ies;
 668                         found->pub.len_information_elements =
 669                                 found->pub.len_proberesp_ies;
 670                 }
 671                 if (res->pub.beacon_ies) {
 672                         size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
 673                         size_t ielen = res->pub.len_beacon_ies;
 674                         bool information_elements_is_beacon_ies =
 675                                 (found->pub.information_elements ==
 676                                  found->pub.beacon_ies);
 677
 678                         if (found->pub.beacon_ies &&
 679                             !found->beacon_ies_allocated &&
 680                             ksize(found) >= used + ielen) {
 681                                 memcpy(found->pub.beacon_ies,
 682                                        res->pub.beacon_ies, ielen);
 683                                 found->pub.len_beacon_ies = ielen;
 684                         } else {
 685                                 u8 *ies = found->pub.beacon_ies;
 686
 687                                 if (found->beacon_ies_allocated)
 688                                         ies = krealloc(ies, ielen, GFP_ATOMIC);
 689                                 else
 690                                         ies = kmalloc(ielen, GFP_ATOMIC);
 691
 692                                 if (ies) {
 693                                         memcpy(ies, res->pub.beacon_ies,
 694                                                ielen);
 695                                         found->beacon_ies_allocated = true;
 696                                         found->pub.beacon_ies = ies;
 697                                         found->pub.len_beacon_ies = ielen;
 698                                 }
 699                         }
 700
 701                         /* Override IEs if they were from a beacon before */
 702                         if (information_elements_is_beacon_ies) {
 703                                 found->pub.information_elements =
 704                                         found->pub.beacon_ies;
 705                                 found->pub.len_information_elements =
 706                                         found->pub.len_beacon_ies;
 707                         }
 708                 }
 709
 710                 kref_put(&res->ref, bss_release);
 711         } else {
 712                 struct cfg80211_internal_bss *hidden;
 713
 714                 /* First check if the beacon is a probe response from
 715                  * a hidden bss. If so, copy beacon ies (with nullified
 716                  * ssid) into the probe response bss entry (with real ssid).
 717                  * It is required basically for PSM implementation
 718                  * (probe responses do not contain tim ie) */
 719
 720                 /* TODO: The code is not trying to update existing probe
 721                  * response bss entries when beacon ies are
 722                  * getting changed. */
 723                 hidden = rb_find_hidden_bss(dev, res);
 724                 if (hidden)
 725                         copy_hidden_ies(res, hidden);
 726
 727                 /* this "consumes" the reference */
 728                 list_add_tail(&res->list, &dev->bss_list);
 729                 rb_insert_bss(dev, res);
 730                 found = res;
 731         }
 732
 733         dev->bss_generation++;
 734         spin_unlock_bh(&dev->bss_lock);
 735
 736         kref_get(&found->ref);
 737         return found;
 738 }
 739
 740 struct cfg80211_bss*
 741 cfg80211_inform_bss(struct wiphy *wiphy,
 742                     struct ieee80211_channel *channel,
 743                     const u8 *bssid, u64 tsf, u16 capability,
 744                     u16 beacon_interval, const u8 *ie, size_t ielen,
 745                     s32 signal, gfp_t gfp)
 746 {
 747         struct cfg80211_internal_bss *res;
 748         size_t privsz;
 749
 750         if (WARN_ON(!wiphy))
 751                 return NULL;
 752
 753         privsz = wiphy->bss_priv_size;
 754
 755         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 756                         (signal < 0 || signal > 100)))
 757                 return NULL;
 758
 759         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 760         if (!res)
 761                 return NULL;
 762
 763         memcpy(res->pub.bssid, bssid, ETH_ALEN);
 764         res->pub.channel = channel;
 765         res->pub.signal = signal;
 766         res->pub.tsf = tsf;
 767         res->pub.beacon_interval = beacon_interval;
 768         res->pub.capability = capability;
 769         /*
 770          * Since we do not know here whether the IEs are from a Beacon or Probe
 771          * Response frame, we need to pick one of the options and only use it
 772          * with the driver that does not provide the full Beacon/Probe Response
 773          * frame. Use Beacon frame pointer to avoid indicating that this should
 774          * override the information_elements pointer should we have received an
 775          * earlier indication of Probe Response data.
 776          *
 777          * The initial buffer for the IEs is allocated with the BSS entry and
 778          * is located after the private area.
 779          */
 780         res->pub.beacon_ies = (u8 *)res + sizeof(*res) + privsz;
 781         memcpy(res->pub.beacon_ies, ie, ielen);
 782         res->pub.len_beacon_ies = ielen;
 783         res->pub.information_elements = res->pub.beacon_ies;
 784         res->pub.len_information_elements = res->pub.len_beacon_ies;
 785
 786         kref_init(&res->ref);
 787
 788         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res);
 789         if (!res)
 790                 return NULL;
 791
 792         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 793                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 794
 795         /* cfg80211_bss_update gives us a referenced result */
 796         return &res->pub;
 797 }
 798 EXPORT_SYMBOL(cfg80211_inform_bss);
 799
 800 struct cfg80211_bss *
 801 cfg80211_inform_bss_frame(struct wiphy *wiphy,
 802                           struct ieee80211_channel *channel,
 803                           struct ieee80211_mgmt *mgmt, size_t len,
 804                           s32 signal, gfp_t gfp)
 805 {
 806         struct cfg80211_internal_bss *res;
 807         size_t ielen = len - offsetof(struct ieee80211_mgmt,
 808                                       u.probe_resp.variable);
 809         size_t privsz;
 810
 811         if (WARN_ON(!mgmt))
 812                 return NULL;
 813
 814         if (WARN_ON(!wiphy))
 815                 return NULL;
 816
 817         if (WARN_ON(wiphy->signal_type == CFG80211_SIGNAL_TYPE_UNSPEC &&
 818                     (signal < 0 || signal > 100)))
 819                 return NULL;
 820
 821         if (WARN_ON(len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
 822                 return NULL;
 823
 824         privsz = wiphy->bss_priv_size;
 825
 826         res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
 827         if (!res)
 828                 return NULL;
 829
 830         memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
 831         res->pub.channel = channel;
 832         res->pub.signal = signal;
 833         res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 834         res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 835         res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
 836         /*
 837          * The initial buffer for the IEs is allocated with the BSS entry and
 838          * is located after the private area.
 839          */
 840         if (ieee80211_is_probe_resp(mgmt->frame_control)) {
 841                 res->pub.proberesp_ies = (u8 *) res + sizeof(*res) + privsz;
 842                 memcpy(res->pub.proberesp_ies, mgmt->u.probe_resp.variable,
 843                        ielen);
 844                 res->pub.len_proberesp_ies = ielen;
 845                 res->pub.information_elements = res->pub.proberesp_ies;
 846                 res->pub.len_information_elements = res->pub.len_proberesp_ies;
 847         } else {
 848                 res->pub.beacon_ies = (u8 *) res + sizeof(*res) + privsz;
 849                 memcpy(res->pub.beacon_ies, mgmt->u.beacon.variable, ielen);
 850                 res->pub.len_beacon_ies = ielen;
 851                 res->pub.information_elements = res->pub.beacon_ies;
 852                 res->pub.len_information_elements = res->pub.len_beacon_ies;
 853         }
 854
 855         kref_init(&res->ref);
 856
 857         res = cfg80211_bss_update(wiphy_to_dev(wiphy), res);
 858         if (!res)
 859                 return NULL;
 860
 861         if (res->pub.capability & WLAN_CAPABILITY_ESS)
 862                 regulatory_hint_found_beacon(wiphy, channel, gfp);
 863
 864         /* cfg80211_bss_update gives us a referenced result */
 865         return &res->pub;
 866 }
 867 EXPORT_SYMBOL(cfg80211_inform_bss_frame);
 868
 869 void cfg80211_ref_bss(struct cfg80211_bss *pub)
 870 {
 871         struct cfg80211_internal_bss *bss;
 872
 873         if (!pub)
 874                 return;
 875
 876         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 877         kref_get(&bss->ref);
 878 }
 879 EXPORT_SYMBOL(cfg80211_ref_bss);
 880
 881 void cfg80211_put_bss(struct cfg80211_bss *pub)
 882 {
 883         struct cfg80211_internal_bss *bss;
 884
 885         if (!pub)
 886                 return;
 887
 888         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 889         kref_put(&bss->ref, bss_release);
 890 }
 891 EXPORT_SYMBOL(cfg80211_put_bss);
 892
 893 void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
 894 {
 895         struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
 896         struct cfg80211_internal_bss *bss;
 897
 898         if (WARN_ON(!pub))
 899                 return;
 900
 901         bss = container_of(pub, struct cfg80211_internal_bss, pub);
 902
 903         spin_lock_bh(&dev->bss_lock);
 904         if (!list_empty(&bss->list)) {
 905                 __cfg80211_unlink_bss(dev, bss);
 906                 dev->bss_generation++;
 907         }
 908         spin_unlock_bh(&dev->bss_lock);
 909 }
 910 EXPORT_SYMBOL(cfg80211_unlink_bss);
 911
 912 #ifdef CONFIG_CFG80211_WEXT
 913 int cfg80211_wext_siwscan(struct net_device *dev,
 914                           struct iw_request_info *info,
 915                           union iwreq_data *wrqu, char *extra)
 916 {
 917         struct cfg80211_registered_device *rdev;
 918         struct wiphy *wiphy;
 919         struct iw_scan_req *wreq = NULL;
 920         struct cfg80211_scan_request *creq = NULL;
 921         int i, err, n_channels = 0;
 922         enum ieee80211_band band;
 923
 924         if (!netif_running(dev))
 925                 return -ENETDOWN;
 926
 927         if (wrqu->data.length == sizeof(struct iw_scan_req))
 928                 wreq = (struct iw_scan_req *)extra;
 929
 930         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
 931
 932         if (IS_ERR(rdev))
 933                 return PTR_ERR(rdev);
 934
 935         if (rdev->scan_req) {
 936                 err = -EBUSY;
 937                 goto out;
 938         }
 939
 940         wiphy = &rdev->wiphy;
 941
 942         /* Determine number of channels, needed to allocate creq */
 943         if (wreq && wreq->num_channels)
 944                 n_channels = wreq->num_channels;
 945         else {
 946                 for (band = 0; band < IEEE80211_NUM_BANDS; band++)
 947                         if (wiphy->bands[band])
 948                                 n_channels += wiphy->bands[band]->n_channels;
 949         }
 950
 951         creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
 952                        n_channels * sizeof(void *),
 953                        GFP_ATOMIC);
 954         if (!creq) {
 955                 err = -ENOMEM;
 956                 goto out;
 957         }
 958
 959         creq->wiphy = wiphy;
 960         creq->wdev = dev->ieee80211_ptr;
 961         /* SSIDs come after channels */
 962         creq->ssids = (void *)&creq->channels[n_channels];
 963         creq->n_channels = n_channels;
 964         creq->n_ssids = 1;
 965
 966         /* translate "Scan on frequencies" request */
 967         i = 0;
 968         for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
 969                 int j;
 970
 971                 if (!wiphy->bands[band])
 972                         continue;
 973
 974                 for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
 975                         /* ignore disabled channels */
 976                         if (wiphy->bands[band]->channels[j].flags &
 977                                                 IEEE80211_CHAN_DISABLED)
 978                                 continue;
 979
 980                         /* If we have a wireless request structure and the
 981                          * wireless request specifies frequencies, then search
 982                          * for the matching hardware channel.
 983                          */
 984                         if (wreq && wreq->num_channels) {
 985                                 int k;
 986                                 int wiphy_freq = wiphy->bands[band]->channels[j].center_freq;
 987                                 for (k = 0; k < wreq->num_channels; k++) {
 988                                         int wext_freq = cfg80211_wext_freq(wiphy, &wreq->channel_list[k]);
 989                                         if (wext_freq == wiphy_freq)
 990                                                 goto wext_freq_found;
 991                                 }
 992                                 goto wext_freq_not_found;
 993                         }
 994
 995                 wext_freq_found:
 996                         creq->channels[i] = &wiphy->bands[band]->channels[j];
 997                         i++;
 998                 wext_freq_not_found: ;
 999                 }
1000         }
1001         /* No channels found? */
1002         if (!i) {
1003                 err = -EINVAL;
1004                 goto out;
1005         }
1006
1007         /* Set real number of channels specified in creq->channels[] */
1008         creq->n_channels = i;
1009
1010         /* translate "Scan for SSID" request */
1011         if (wreq) {
1012                 if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
1013                         if (wreq->essid_len > IEEE80211_MAX_SSID_LEN) {
1014                                 err = -EINVAL;
1015                                 goto out;
1016                         }
1017                         memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
1018                         creq->ssids[0].ssid_len = wreq->essid_len;
1019                 }
1020                 if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
1021                         creq->n_ssids = 0;
1022         }
1023
1024         for (i = 0; i < IEEE80211_NUM_BANDS; i++)
1025                 if (wiphy->bands[i])
1026                         creq->rates[i] = (1 << wiphy->bands[i]->n_bitrates) - 1;
1027
1028         rdev->scan_req = creq;
1029         err = rdev->ops->scan(wiphy, creq);
1030         if (err) {
1031                 rdev->scan_req = NULL;
1032                 /* creq will be freed below */
1033         } else {
1034                 nl80211_send_scan_start(rdev, dev->ieee80211_ptr);
1035                 /* creq now owned by driver */
1036                 creq = NULL;
1037                 dev_hold(dev);
1038         }
1039  out:
1040         kfree(creq);
1041         cfg80211_unlock_rdev(rdev);
1042         return err;
1043 }
1044 EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
1045
1046 static void ieee80211_scan_add_ies(struct iw_request_info *info,
1047                                    struct cfg80211_bss *bss,
1048                                    char **current_ev, char *end_buf)
1049 {
1050         u8 *pos, *end, *next;
1051         struct iw_event iwe;
1052
1053         if (!bss->information_elements ||
1054             !bss->len_information_elements)
1055                 return;
1056
1057         /*
1058          * If needed, fragment the IEs buffer (at IE boundaries) into short
1059          * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
1060          */
1061         pos = bss->information_elements;
1062         end = pos + bss->len_information_elements;
1063
1064         while (end - pos > IW_GENERIC_IE_MAX) {
1065                 next = pos + 2 + pos[1];
1066                 while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
1067                         next = next + 2 + next[1];
1068
1069                 memset(&iwe, 0, sizeof(iwe));
1070                 iwe.cmd = IWEVGENIE;
1071                 iwe.u.data.length = next - pos;
1072                 *current_ev = iwe_stream_add_point(info, *current_ev,
1073                                                    end_buf, &iwe, pos);
1074
1075                 pos = next;
1076         }
1077
1078         if (end > pos) {
1079                 memset(&iwe, 0, sizeof(iwe));
1080                 iwe.cmd = IWEVGENIE;
1081                 iwe.u.data.length = end - pos;
1082                 *current_ev = iwe_stream_add_point(info, *current_ev,
1083                                                    end_buf, &iwe, pos);
1084         }
1085 }
1086
1087 static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
1088 {
1089         unsigned long end = jiffies;
1090
1091         if (end >= start)
1092                 return jiffies_to_msecs(end - start);
1093
1094         return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
1095 }
1096
1097 static char *
1098 ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
1099               struct cfg80211_internal_bss *bss, char *current_ev,
1100               char *end_buf)
1101 {
1102         struct iw_event iwe;
1103         u8 *buf, *cfg, *p;
1104         u8 *ie = bss->pub.information_elements;
1105         int rem = bss->pub.len_information_elements, i, sig;
1106         bool ismesh = false;
1107
1108         memset(&iwe, 0, sizeof(iwe));
1109         iwe.cmd = SIOCGIWAP;
1110         iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
1111         memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
1112         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1113                                           IW_EV_ADDR_LEN);
1114
1115         memset(&iwe, 0, sizeof(iwe));
1116         iwe.cmd = SIOCGIWFREQ;
1117         iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
1118         iwe.u.freq.e = 0;
1119         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1120                                           IW_EV_FREQ_LEN);
1121
1122         memset(&iwe, 0, sizeof(iwe));
1123         iwe.cmd = SIOCGIWFREQ;
1124         iwe.u.freq.m = bss->pub.channel->center_freq;
1125         iwe.u.freq.e = 6;
1126         current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
1127                                           IW_EV_FREQ_LEN);
1128
1129         if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
1130                 memset(&iwe, 0, sizeof(iwe));
1131                 iwe.cmd = IWEVQUAL;
1132                 iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
1133                                      IW_QUAL_NOISE_INVALID |
1134                                      IW_QUAL_QUAL_UPDATED;
1135                 switch (wiphy->signal_type) {
1136                 case CFG80211_SIGNAL_TYPE_MBM:
1137                         sig = bss->pub.signal / 100;
1138                         iwe.u.qual.level = sig;
1139                         iwe.u.qual.updated |= IW_QUAL_DBM;
1140                         if (sig < -110)         /* rather bad */
1141                                 sig = -110;
1142                         else if (sig > -40)     /* perfect */
1143                                 sig = -40;
1144                         /* will give a range of 0 .. 70 */
1145                         iwe.u.qual.qual = sig + 110;
1146                         break;
1147                 case CFG80211_SIGNAL_TYPE_UNSPEC:
1148                         iwe.u.qual.level = bss->pub.signal;
1149                         /* will give range 0 .. 100 */
1150                         iwe.u.qual.qual = bss->pub.signal;
1151                         break;
1152                 default:
1153                         /* not reached */
1154                         break;
1155                 }
1156                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1157                                                   &iwe, IW_EV_QUAL_LEN);
1158         }
1159
1160         memset(&iwe, 0, sizeof(iwe));
1161         iwe.cmd = SIOCGIWENCODE;
1162         if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
1163                 iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
1164         else
1165                 iwe.u.data.flags = IW_ENCODE_DISABLED;
1166         iwe.u.data.length = 0;
1167         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1168                                           &iwe, "");
1169
1170         while (rem >= 2) {
1171                 /* invalid data */
1172                 if (ie[1] > rem - 2)
1173                         break;
1174
1175                 switch (ie[0]) {
1176                 case WLAN_EID_SSID:
1177                         memset(&iwe, 0, sizeof(iwe));
1178                         iwe.cmd = SIOCGIWESSID;
1179                         iwe.u.data.length = ie[1];
1180                         iwe.u.data.flags = 1;
1181                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1182                                                           &iwe, ie + 2);
1183                         break;
1184                 case WLAN_EID_MESH_ID:
1185                         memset(&iwe, 0, sizeof(iwe));
1186                         iwe.cmd = SIOCGIWESSID;
1187                         iwe.u.data.length = ie[1];
1188                         iwe.u.data.flags = 1;
1189                         current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1190                                                           &iwe, ie + 2);
1191                         break;
1192                 case WLAN_EID_MESH_CONFIG:
1193                         ismesh = true;
1194                         if (ie[1] != sizeof(struct ieee80211_meshconf_ie))
1195                                 break;
1196                         buf = kmalloc(50, GFP_ATOMIC);
1197                         if (!buf)
1198                                 break;
1199                         cfg = ie + 2;
1200                         memset(&iwe, 0, sizeof(iwe));
1201                         iwe.cmd = IWEVCUSTOM;
1202                         sprintf(buf, "Mesh Network Path Selection Protocol ID: "
1203                                 "0x%02X", cfg[0]);
1204                         iwe.u.data.length = strlen(buf);
1205                         current_ev = iwe_stream_add_point(info, current_ev,
1206                                                           end_buf,
1207                                                           &iwe, buf);
1208                         sprintf(buf, "Path Selection Metric ID: 0x%02X",
1209                                 cfg[1]);
1210                         iwe.u.data.length = strlen(buf);
1211                         current_ev = iwe_stream_add_point(info, current_ev,
1212                                                           end_buf,
1213                                                           &iwe, buf);
1214                         sprintf(buf, "Congestion Control Mode ID: 0x%02X",
1215                                 cfg[2]);
1216                         iwe.u.data.length = strlen(buf);
1217                         current_ev = iwe_stream_add_point(info, current_ev,
1218                                                           end_buf,
1219                                                           &iwe, buf);
1220                         sprintf(buf, "Synchronization ID: 0x%02X", cfg[3]);
1221                         iwe.u.data.length = strlen(buf);
1222                         current_ev = iwe_stream_add_point(info, current_ev,
1223                                                           end_buf,
1224                                                           &iwe, buf);
1225                         sprintf(buf, "Authentication ID: 0x%02X", cfg[4]);
1226                         iwe.u.data.length = strlen(buf);
1227                         current_ev = iwe_stream_add_point(info, current_ev,
1228                                                           end_buf,
1229                                                           &iwe, buf);
1230                         sprintf(buf, "Formation Info: 0x%02X", cfg[5]);
1231                         iwe.u.data.length = strlen(buf);
1232                         current_ev = iwe_stream_add_point(info, current_ev,
1233                                                           end_buf,
1234                                                           &iwe, buf);
1235                         sprintf(buf, "Capabilities: 0x%02X", cfg[6]);
1236                         iwe.u.data.length = strlen(buf);
1237                         current_ev = iwe_stream_add_point(info, current_ev,
1238                                                           end_buf,
1239                                                           &iwe, buf);
1240                         kfree(buf);
1241                         break;
1242                 case WLAN_EID_SUPP_RATES:
1243                 case WLAN_EID_EXT_SUPP_RATES:
1244                         /* display all supported rates in readable format */
1245                         p = current_ev + iwe_stream_lcp_len(info);
1246
1247                         memset(&iwe, 0, sizeof(iwe));
1248                         iwe.cmd = SIOCGIWRATE;
1249                         /* Those two flags are ignored... */
1250                         iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
1251
1252                         for (i = 0; i < ie[1]; i++) {
1253                                 iwe.u.bitrate.value =
1254                                         ((ie[i + 2] & 0x7f) * 500000);
1255                                 p = iwe_stream_add_value(info, current_ev, p,
1256                                                 end_buf, &iwe, IW_EV_PARAM_LEN);
1257                         }
1258                         current_ev = p;
1259                         break;
1260                 }
1261                 rem -= ie[1] + 2;
1262                 ie += ie[1] + 2;
1263         }
1264
1265         if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS) ||
1266             ismesh) {
1267                 memset(&iwe, 0, sizeof(iwe));
1268                 iwe.cmd = SIOCGIWMODE;
1269                 if (ismesh)
1270                         iwe.u.mode = IW_MODE_MESH;
1271                 else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
1272                         iwe.u.mode = IW_MODE_MASTER;
1273                 else
1274                         iwe.u.mode = IW_MODE_ADHOC;
1275                 current_ev = iwe_stream_add_event(info, current_ev, end_buf,
1276                                                   &iwe, IW_EV_UINT_LEN);
1277         }
1278
1279         buf = kmalloc(30, GFP_ATOMIC);
1280         if (buf) {
1281                 memset(&iwe, 0, sizeof(iwe));
1282                 iwe.cmd = IWEVCUSTOM;
1283                 sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
1284                 iwe.u.data.length = strlen(buf);
1285                 current_ev = iwe_stream_add_point(info, current_ev, end_buf,
1286                                                   &iwe, buf);
1287                 memset(&iwe, 0, sizeof(iwe));
1288                 iwe.cmd = IWEVCUSTOM;
1289                 sprintf(buf, " Last beacon: %ums ago",
1290                         elapsed_jiffies_msecs(bss->ts));
1291                 iwe.u.data.length = strlen(buf);
1292                 current_ev = iwe_stream_add_point(info, current_ev,
1293                                                   end_buf, &iwe, buf);
1294                 kfree(buf);
1295         }
1296
1297         ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
1298
1299         return current_ev;
1300 }
1301
1302
1303 static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
1304                                   struct iw_request_info *info,
1305                                   char *buf, size_t len)
1306 {
1307         char *current_ev = buf;
1308         char *end_buf = buf + len;
1309         struct cfg80211_internal_bss *bss;
1310
1311         spin_lock_bh(&dev->bss_lock);
1312         cfg80211_bss_expire(dev);
1313
1314         list_for_each_entry(bss, &dev->bss_list, list) {
1315                 if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
1316                         spin_unlock_bh(&dev->bss_lock);
1317                         return -E2BIG;
1318                 }
1319                 current_ev = ieee80211_bss(&dev->wiphy, info, bss,
1320                                            current_ev, end_buf);
1321         }
1322         spin_unlock_bh(&dev->bss_lock);
1323         return current_ev - buf;
1324 }
1325
1326
1327 int cfg80211_wext_giwscan(struct net_device *dev,
1328                           struct iw_request_info *info,
1329                           struct iw_point *data, char *extra)
1330 {
1331         struct cfg80211_registered_device *rdev;
1332         int res;
1333
1334         if (!netif_running(dev))
1335                 return -ENETDOWN;
1336
1337         rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
1338
1339         if (IS_ERR(rdev))
1340                 return PTR_ERR(rdev);
1341
1342         if (rdev->scan_req) {
1343                 res = -EAGAIN;
1344                 goto out;
1345         }
1346
1347         res = ieee80211_scan_results(rdev, info, extra, data->length);
1348         data->length = 0;
1349         if (res >= 0) {
1350                 data->length = res;
1351                 res = 0;
1352         }
1353
1354  out:
1355         cfg80211_unlock_rdev(rdev);
1356         return res;
1357 }
1358 EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
1359 #endif